BPMN Business Process Model Notation – Process Modeling, Events, Gateways, Tasks

This article is a definition of terms for BPMN – including exam questions and tags.

In a Nutshell

BPMN (Business Process Model and Notation) is a graphical standard for modeling business processes that provides a unified language for business analysts, technicians, and managers.

Compact Technical Description

BPMN is a notation developed by the Object Management Group (OMG) for visualizing business processes. It uses a standardized graphical representation with flow objects (Events, Activities, Gateways), connectors (Sequence Flows, Message Flows), and swimlanes (Pools, Lanes). BPMN 2.0 supports both process modeling and process executability. The notation distinguishes between start, intermediate, and end events, various task types, and gateway types for decisions and branching. BPMN enables the bridge between business process description and technical implementation.

Exam-Relevant Key Points

• Flow objects: Events (circles), Activities (rectangles), Gateways (diamonds)
• Events: Start Events (beginning), Intermediate Events (during), End Events (end)
• Tasks: User Task, Service Task, Script Task, Manual Task
• Gateways: Exclusive Gateway (XOR), Parallel Gateway (AND), Inclusive Gateway (OR)
• Swimlanes: Pools (participants), Lanes (roles/departments)
• Connectors: Sequence Flow (within), Message Flow (between pools)
• Data objects: Data Objects, Data Stores, Data Inputs/Outputs
• Chamber of Commerce relevant: Reading BPMN diagrams and modeling simple processes

Core Components

1. Events (Start, Intermediate, End)
2. Activities (Tasks, Sub-Processes)
3. Gateways (Exclusive, Parallel, Inclusive, Complex)
4. Sequence Flows and Message Flows
5. Pools and Lanes (Swimlanes)
6. Data Objects and Data Stores
7. Artifacts (Text Annotation, Group)
8. Connecting Objects (Associations)
9. Sub-Processes and Call Activities
10. Process Hierarchies and Decomposition

Practical Example

// Simplified order process in BPMN
Pool: "Customer"
- Start Event: "Place order"
- User Task: "Select items"
- User Task: "Enter delivery address"
- End Event: "Order confirmed"

Pool: "Sales"
- Start Event: "Order received" (Message Event)
- Service Task: "Check availability"
- Exclusive Gateway: "Items available?"
  - Yes: User Task: "Create invoice"
  - No: User Task: "Inform customer"
- End Event: "Order completed"

Sequence Flows connect the elements within the pools.
Message Flows show communication between customer and sales.

Advantages and Disadvantages

Advantages

• Unified language for all stakeholders
• Graphical representation facilitates understanding
• Standardized and internationally recognized
• Supports process automation and optimization

Disadvantages

• Complex processes can become confusing
• Learning curve for all notation elements
• Risk of over-modeling
• Tool dependency for complex models

Typical Exam Questions (with Short Answer)

1. Three main types of flow objects in BPMN? Events (circles), Activities (rectangles), Gateways (diamonds).

2. Difference between Sequence Flow and Message Flow? Sequence Flow connects elements within a pool, Message Flow between different pools.

3. Exclusive Gateway (XOR) meaning? Exactly one path is selected based on conditions.

4. User Task vs. Service Task? User Task is performed by people, Service Task is automated by systems.

5. Start Event vs. End Event? Start Event initiates process, End Event terminates process.

6. Pool vs. Lane in BPMN? Pool represents a participant (organization), Lane subdivides pool into roles/departments.

7. Parallel Gateway (AND) usage? When multiple paths should be executed simultaneously.

8. Data Object purpose in BPMN? Represents information needed or produced by the process.

Most Important Sources

1. https://www.omg.org/spec/BPMN/
2. https://de.wikipedia.org/wiki/Business_Process_Model_and_Notation
3. https://www.bpmn.org/